The present invention relates to communication systems, and is particularly directed to an exciter useable for a plurality of communication formats.
With the advent of digital television (xe2x80x9cDTVxe2x80x9d) broadcasting, it is apparent that there will be at least two format standards utilized. Within the United States, the Federal Communication Commission (xe2x80x9cFCCxe2x80x9d) has adopted an eight vestigial sideband (xe2x80x9c8VSBxe2x80x9d) format. Elsewhere within the world, a coded orthogonal frequency division and multiplexing (xe2x80x9cCOFDMxe2x80x9d) format has been adopted.
Also, current analog television systems exist under either the National Television System Committee (xe2x80x9cNTSCxe2x80x9d, U.S. and Japan) format or the Phase Alternation by Line (xe2x80x9cPALxe2x80x9d, elsewhere) format. Further, various other transmission formats exist.
Examples of such transmission formats include Frequency Modulation (xe2x80x9cFMxe2x80x9d), Amplitude Modulation (xe2x80x9cAMxe2x80x9d), Digital Audio Broadcast (xe2x80x9cDABxe2x80x9d), Quadrature Amplitude Modulation (xe2x80x9cQAMxe2x80x9d), Code Division Multiple Access (xe2x80x9cCDMAxe2x80x9d), and Time Division Multiple Access (xe2x80x9cTDMAxe2x80x9d).
Each of these different types of transmission use various types of modulation, occupy different bandwidths, and/or operate on different frequencies (channels). Digital systems that would be used within each of these types of transmission systems differ in their implementation details. For example, a comparison of the 8VSB and COFDM digital television formats indicate that there are differences relating to data rates, parity bits, block size and other parameters.
However, despite the differences, transmission systems of the various formats have certain characteristics that are common. From the standpoint of a manufacturer of broadcast transmission equipment, it would be beneficial to capitalize on the common aspects of the various types of transmission formats. This would allow a manufacturer to capitalize on economies of scale regarding manufacture of various transmission format systems.
In accordance with one aspect, the present invention provides an exciter, located along an information stream path of a transmission system, for supplying an information signal as a drive to an amplifying arrangement. Coder means outputs the information signal that conveys data and a desired code arrangement. Filter means restricts the energy of the signal to a predetermined channel bandwidth. Modulator means modulates the baseband information signal. Corrector/equalizer means pre-corrects the modulated signal for errors induced in the transmission system. At least two of the coder means, the filter means, the modulator means, and the corrector/equalizer means are programmable to be operative in any of several I/O formats. Controller means provides program control of at least two of the coder means, the filter means, the modulator means, and the corrector/equalizer means.
In accordance with another aspect, the present invention provides an exciter, located along an information stream path of a transmission system, for supplying an information signal as a drive to an amplifying arrangement. Filter means, programmable to be operative in any of several I/O formats, confines the signal energy to a predetermined channel bandwidth. Modulator means, programmable to be operative in any of several I/O formats, modulates the baseband signal. Corrector/equalizer means, programmable to be operative in any of several I/O formats, pre-corrects the modulated signal for errors induced in the transmission system. Controller means provides program control of the filter means, the modulator means, and the corrector/equalizer means.
In accordance with another aspect, the present invention provides an exciter, located along an information stream path of a transmission system, for supplying an information signal as a drive to an amplifying arrangement. Coder means, programmable to be operative in any of several I/O formats, outputs the information signal that conveys data and a desired code arrangement. Modulator means, programmable to be operative in any of several I/O formats, modulates the baseband signal. Corrector/equalizer means, programmable to be operative in any of several I/O formats, pre-corrects the modulated signal for errors induced in the transmission system. Controller means provides program control of the coder means, the modulator means, and the corrector/equalizer means.
In accordance with yet another aspect, the present invention provides an exciter, located along an information stream path of a transmission system, for supplying an information signal as a drive to an amplifying arrangement. Coder means, programmable to be operative in any of several I/O formats, outputs the information signal that conveys data and a desired code arrangement. Filter means, programmable to be operative in any of several I/O formats, confines the signal energy to a predetermined channel bandwidth. Corrector/equalizer means, programmable to be operative in any of several I/O formats, pre-corrects the modulated signal for errors induced in the transmission system. Controller means provides program control of the coder means, the filter means, and the corrector/equalizer means.
In accordance with still another aspect, the present invention provides an exciter, located along an information stream path of a transmission system, for supplying an information signal as a drive to an amplifying arrangement. Coder means, programmable to be operative in any of several I/O formats, outputs the information signal that conveys data and a desired code arrangement. Filter means, programmable to be operative in any of several I/O formats, confines the signal energy to a predetermined channel bandwidth. Modulator means, programmable to be operative in any of several I/O formats, modulates the baseband signal. Controller means provides program control of the coder means, the filter means, and the modulator means.
In accordance with still another aspect, the present invention provides an exciter, located along an information stream path of a transmission system, for supplying an information signal as a drive to an amplifying arrangement. Coder means, programmable to be operative in any of several I/O formats, outputs the information signal that conveys data and a desired code arrangement. Filter means, programmable to be operative in any of several I/O formats, confines the signal energy to a predetermined channel bandwidth. Modulator means, programmable to be operative in any of several I/O formats, modulates the baseband signal. Corrector/equalizer means, programmable to be operative in any of several I/O formats, pre-corrects the modulated signal for errors induced in the transmission system. Controller means provides program control of the coder means, the filter means, the modulator means, and the corrector/equalizer means.